278
FXUS62 KMLB 131851
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
251 PM EDT Sun Jul 13 2025

...New KEY MESSAGES, DISCUSSION, MARINE...

.KEY MESSAGES...
Issued at 240 PM EDT Sun Jul 13 2025

- A disturbance and associated deep moisture moves over central
  Florida early this week. Above-normal lightning storm chances
  and locally heavy rainfall with be the primary impacts.

- Daily rain chances remain high, up to around 80% through midweek
  as the disturbance continues to pull deep moisture over the
  peninsula as it moves into the Gulf.

- Hot and humid conditions with peak heat index values between 102
  to 107 degrees continue today; residents and visitors are
  encouraged to stay cool and well-hydrated to avoid heat-related
  illness.

&&

.DISCUSSION...
Issued at 240 PM EDT Sun Jul 13 2025

Currently...High clouds have reduced effectiveness of daytime
heating some, slowing development of the east coast sea breeze.
KMLB radar is even still showing offshore flow along much of the
coast. Storms in the Gulf near the Nature Coast this morning have
pushed outflow inland and into the northern counties, which has
reached the Volusia and northern Brevard coasts and is supporting
strong to severe thunderstorms. Storms have also developed along
the southern coast where the east coast sea breeze has managed to
develop.

Rest of Today...Increasing moisture pushing southeast into the
area along a broad surface trough is still expected to support
high chances for showers and storms. Convection will continue to
develop along the sea breezes and other boundaries while generally
pushing to the south to southeast. Some locations could even see
a couple rounds of storms this afternoon and evening, notably the
Orlando and Daytona Beach areas, as storms developing in North
Florida travel southward along the trough. Despite the slow
destabilization, the environment remains supportive of strong
thunderstorms, especially closer to the trough, capable of gusty
winds to 55 mph, frequent cloud to ground lightning, small hail,
and torrential downpours. There is a Marginal (level 1 of 5) risk
for severe thunderstorms, capable of locally damaging wind gusts
around 60 mph (5% chance), and a very low (less than 2%) chance
for hail up to 1". While most storms will move slowly to the south
to southeast, chaotic boundary interactions could cause some to
become slow and erratic, resulting in locally high rainfall
leading to ponding of water on roads and minor flooding of low-
lying or poor drainage areas. Given the high moisture and boundary
interactions, there is potential for a few funnel clouds as well.
Despite the high clouds, high temperatures still climb into the
L90s, which combined with humidity will bring peak afternoon heat
indices o 101-107.

Monday-Tuesday... (Modified Previous Discussion) A weak 500mb
trough moves across the southwest Atlantic Monday, passing over
the Florida peninsula on Tuesday. A broad surface trough offshore
the southeast U.S. coast attempts to become more organized with
passing mid level support, developing a weak low in the vicinity
of Florida. Waves of anomalously high moisture move through the
region each day with modeled PWATs as high as 2.1-2.2", and values
range above the 90th climatological percentile. High moisture in
vicinity of weak mid level support will continue to fuel high rain
chances each day (~80%), and a heavy rainfall threat will remain
present. While global ensemble guidance suggests daily areawide
totals of 0.5-1.5", localized totals of 2-4" remain in play both
days. Areas that receive these localized higher totals over
multiple days will become vulnerable to minor flooding. Although
increased cloud cover may limit surface instability, tall skinny
CAPE profiles around 2,000 J/kg and vorticity aloft suggest at
least an isolated strong storm threat. Stronger storms will be
capable of occasional to frequent lightning strikes and water
loaded downdrafts which can produce localized gusty winds.

Temperatures trend a few degrees cooler Monday and Tuesday,
corresponding to higher rain chances and cloud cover. Highs in the
upper 80s to low 90s Monday range the mid to upper 80s by
Tuesday. Morning low temperatures hold steady in the low to mid
70s.

Wednesday-Saturday...(Modified Previous Discussion) The weak area
of low pressure is nudged into the Gulf on Wednesday as the
Atlantic high builds back toward Florida. As the low pressure
departs westward, the National Hurricane Center has highlighted a
20% chance of tropical development into the middle to late part of
the week. Regardless of development deep moisture on the east side
of the feature keeps rain chances high through mid week (70-80%).
By late week and into the weekend, the Atlantic ridge axis takes
control, favoring a more typical summertime pattern with rain
chances trending closer to normal.

&&

.MARINE...
Issued at 240 PM EDT Sun Jul 13 2025

A broad trough of low pressure moves across the local Atlantic
waters early this week. Increased moisture in vicinity of this
feature will keep high daily rain chances (~60-80%) into midweek.
Light offshore flow today continues Monday as the system tracks
across North and Central Florida, then southerly flow develops
from Tuesday onwards as the system departs in the Gulf and the
Atlantic ridge axis begins to gradually rebuild over the local
waters. High cloud cover could delay or even prevent development
of the east coast sea breeze, especially today and Monday. Seas
around 1-3 ft. Locally higher winds and seas in vicinity of
thunderstorms.

&&

.AVIATION...
(18Z TAFs)
Issued at 140 PM EDT Sun Jul 13 2025

Scattered showers and storms have pushed in from the west and is
currently moving towards DAB. Latest CAMs show a couple rounds of
convection today, with the first round happening now and
continuing into late afternoon with the sea breeze, and the
second coming into early evening as the trough moves southward.
Have maintained afternoon TEMPOS with MVFR conditions for TSRA
this afternoon, starting 20/21Z across the interior, and 18/19Z
along the coast, as well as the secondary TEMPOs for this evening
for ISM and LEE starting at 00Z. Convection will diminish first
along the coast around sunset, and then across the interior around
05Z. Light and variable winds overnight will become WNW and
increase to 5-8KT by mid morning. Cams are showing scattered
showers pushing down from the north Monday morning, so have
included VCSH starting at 14Z for interior TAFs. Scattered
lightning storms will then form in the afternoon, so have included
VCTS for MCO starting at 18Z.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  74  91  75  88 /  50  60  30  70
MCO  75  92  75  89 /  60  80  40  80
MLB  74  88  75  87 /  60  70  40  80
VRB  72  88  72  88 /  70  80  50  80
LEE  76  92  75  90 /  60  80  40  80
SFB  76  92  75  90 /  60  80  30  80
ORL  76  92  75  90 /  60  80  40  80
FPR  72  88  72  87 /  70  80  50  80

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&

$$

DISCUSSION...Haley
AVIATION...Watson